Update default value documentation for IncludeWorkItemtypes, SourceFieldMappings, FixedTargetFields, and Enabled properties for clarity

Author: MrHinsh

src/MigrationTools.Clients.TfsObjectModel/Tools/TfsWorkItemTypeValidatorToolOptions.cs

@@ -18,14 +18,15 @@ public class TfsWorkItemTypeValidatorToolOptions : ToolOptions
         /// <summary>
         /// List of work item types which will be validated. If this list is empty, all work item types will be validated.
         /// </summary>
-        /// <default>All work item types are included.</default>
+        /// <default>null</default>
         public List<string> IncludeWorkItemtypes { get; set; } = [];
 
         /// <summary>
         /// Field reference name mappings. Key is work item type name, value is dictionary of mapping source filed name to
         /// target field name. Target field name can be empty string to indicate that this field will not be validated in target.
         /// As work item type name, you can use <c>*</c> to define mappings which will be applied to all work item types.
         /// </summary>
+        /// <default>null</default>
         public Dictionary<string, Dictionary<string, string>> SourceFieldMappings { get; set; } = [];
 
         /// <summary>
@@ -43,6 +44,7 @@ public class TfsWorkItemTypeValidatorToolOptions : ToolOptions
         /// You can also use <c>*</c> to define fixed fields that apply to all work item types.  
         /// </para>
         /// </summary>
+        /// <default>null</default>
         public Dictionary<string, List<string>> FixedTargetFields { get; set; } = [];
 
         /// <summary>

src/MigrationTools/Tools/Infrastructure/ToolOptions.cs

@@ -24,6 +24,7 @@ public abstract class ToolOptions : IToolOptions
         /// <summary>
         /// If set to `true` then the tool will run. Set to `false` and the processor will not run.
         /// </summary>
+        /// <default>true</default>
 
         public bool Enabled { get; set; }